Wiki isn't right about library edition Issue 3 at least. It says here (don't open the link, the cover pic is spoilery) that it contains 3 web comics (titles tagged as potentially spoilery)

Harmony Bites, Harmony Comes to the Nation and Vampy Cat Play Friend

that take place around issues 21-22.

If they're including the web comics, I assume that they're including the one-shots as well and Wikipedia just has incomplete info, since those library issues haven't been released yet. My guess is that the Willow one-shot is in Issue 1 or 2, and the Riley one in Issue 4.

Thanks. What I'm mainly concerned with is if any of the two versions (library of TPB) contains more material than the other. The library edition has also a lot (all?) of the covers collected at the end and a bunch of sketches. Perhaps that's the only difference. On the other hand, this doesn't mention the Willow or Riley one-shot in vol. 2, and your link (I'd seen that cover already, but thanks for the spoiler warning; it's appreciated) doesn't list if for vol. 3 either, so that would mean then that they both have to be in vol. 4?

As for the second one shot included in the library edition vol. 1, I think they mean one-shot as opposed to multi-issue arc, not opposed to regular series issue. So that would make "The Chain" the second one-shot. That confused me at first as well.

Edited to add: Actually, by that reasoning, the two arcs in vol. 1 are "The Long Way Home" and "No Future for You" and the one-shots are "The Chain" and "Anywhere but Here". "Always Darkest" is perhaps not counted in that at all, since it's just a three-page story. It's in there as well though.

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